User:Base/Scripts/DeleteAllPagesInThisCategory.js

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var api = new mw.Api();
var reason = prompt('Why would you want to delete those again?');

api.get({
        action: 'query',
        meta: 'tokens'
    }).done(function(data) {
            console.log(data);
            var token = data.query.tokens.csrftoken;

            api.get({
                action: 'query',
                list: 'categorymembers',
                cmtitle: mw.config.get('wgPageName'),
                cmlimit: 'max'
            }).done(function(data) {
                //   console.log(data);
                $.each(data.query.categorymembers, function() {
                    var page = this;

                    api.post({
                        action: 'delete',
                        pageid: page.pageid,
                        reason: reason,
                        token: token
                    }).done(function(data){
                        console.log(page.title + ' must have been deleted');
                    })
                })
            });
        });